Reproducibility of Laser Doppler Flowmetry in gingival microcirculation. A study on six different protocols

Area of Science:

• Biomedical Engineering
• Microcirculation Research
• Dental Physiology

Background:

• Laser Doppler Flowmetry (LDF) is a key non-invasive method for assessing tissue perfusion.
• Improving the reproducibility of LDF is crucial for reliable longitudinal studies of microvascular function.
• Gingival microcirculation assessment is important for understanding periodontal health and disease.

Purpose of the Study:

• To evaluate the interday reproducibility of Laser Doppler Flowmetry (LDF) in the gingiva.
• To compare the reproducibility of LDF under various conditions: rest, elevated temperatures, and with Methyl Nicotinate (MN) vasodilation.
• To establish optimal protocols for reproducible gingival blood flow measurements.

Main Methods:

• Ten healthy volunteers participated in the study.
• Interweek LDF measurements were conducted using custom-made acrylic splints for stability.
• Six protocols were applied, including basal flow, thermal stimulation (42°C, 45°C), and topical Methyl Nicotinate (MN) application.

Main Results:

• Basal LDF measurements exhibited high reproducibility (wCV 10.3-11.1%, ICC 0.90-0.92).
• LDF measurements with thermal and vasodilatory stimuli showed good reproducibility (wCV 4.9-10.3%, ICC 0.82-0.93).
• Topical Methyl Nicotinate (MN) application resulted in increased gingival blood flow.

Conclusions:

• This study is the first to assess LDF reproducibility with vasodilatory stimuli in the gingiva.
• Recommendations include using multiple collector fiber probes and stabilizing acrylic splints.
• Vasodilatory stimulation, particularly with MN, shows potential for enhancing LDF reproducibility in gingival microcirculation studies.